The present invention relates to orally administrable pharmaceutical compositions containing a slightly water-soluble drug. The pharmaceutical compositions for oral use according to the present invention are based on the characteristic properties of improved absorption from digestive tract into blood and improved stability.
Due to poor absorption of slightly water-soluble drugs, particularly dihydropyridine derivatives and lipoxygenase inhibitors, from digestive tract, there has been a strong demand for the development of pharmaceutical formulations which afford good absorption in clinical applications. In order to improve absorption, addition of an absorbefacient, improvement of dosage form designs, etc. are necessary, and generally employed means of formulation are pulverization of crystals, noncrystallization, addition of surfactants, cyclodextrin inclusion, emulsification, dissolution in polyethylene glycol, vegetable oil, etc., or the like. However, none of these affords sufficient absorption from digestive tract.
In addition, dihydropyridine derivatives are specifically unstable to light, and for this reason, they are prepared into light-resistant preparations or colored preparations and stored in light-resistant containers.